Exercise Physiology Commons^™

The Emerging And Evolving Evidence Supporting Creatine As An Ergogenic Aid: History And Applications, Chad Kerksick, Drew Gonzalez, Jeffrey Stout, Scott Forbes, Darren Candow, Tim Ziegenfuss, Ronald Marshall, René Schwesig, Richard Kreider

Faculty Scholarship

Background

Creatine is one of the most extensively studied ergogenic aids, with over three decades of research supporting its role in exercise performance, recovery, and health.

Methods

This narrative review summarizes the historical development of creatine supplementation and evaluates evidence regarding its mechanisms, efficacy across active, athletic populations (e.g. strength, endurance, team-sport), and tactical (e.g. military, law enforcement) populations, and its safety profile.

Results

The evidence suggests that creatine enhances phosphocreatine resynthesis and cellular energy availability, resulting in consistent improvements in high-intensity exercise performance, training adaptations, lean body mass, strength, and power. Additional findings indicate that creatine may attenuate exercise-induced …

Differences In Fitness Between Cadet And General Population Firefighter Academy Recruits, Scott D. Brau, David Cornell, Benjamin J. Mendelson, Rudi A. Marciniak, Kyle Ebersole

International Journal of Exercise Science

International Journal of Exercise Science 18(8): 774-793, 2025. This longitudinal study explored entry route- and age-related fitness differences between cadet (CR) and general population (GR) firefighter recruits. Fitness data were collected from eight separate firefighter recruit academy cohorts (N = 317; 122 CR, 195 GR; 27.17 ± 7.58 yrs, 177.30 ± 8.72 cm, 88.65 ± 17.78 kg). In the first week of the academy, recruits completed an assessment battery including: body composition via skinfold measures to estimate body fat (BF, %) and fat-free mass (FFM, kg); aerobic fitness (VO_2peak, mL· kg^-1· min^-1) and …

Physiological And Biomechanical Responses To Indoor Cycling With And Without The Ability To Sway, Alina P. Swafford, James W. Navalta, Julia Freedman Silvernail, Nancy Lough, John A. Mercer

International Journal of Exercise Science

International Journal of Exercise Science 18(7): 531-542, 2025. The purpose of this study was to understand whether or not physiological and biomechanical measures were influenced by cycling sway and intensity. Participants (n=13; 24.9±6.5 years; 1.7±0.1 m; 64.7±11.2 kg) completed two submaximal-effort cycling conditions using a stationary smart bike placed on a rocker board: 1) cycling with the rocker board set to allow sway (unblocked); 2) cycling with blocks placed in the rocker board to prevent sway (blocked). The order conditions were counterbalanced, and each condition was 12-mins. For each condition, four intensity levels were completed. Prior to testing, target power …

Compressive Pantyhose Mitigates Muscle Fatigue In Ballet-Specific Test: A Pilot Study, Gustavo R. Mota, Jeffer Eidi Sasaki, Mirelly Rangel Rocha, Pedro Augusto Bianchi Da Fonseca, Bernardo Ide, Kazushige Goto, Donizete Oliveira, Moacir Marocolo

International Journal of Exercise Science

International Journal of Exercise Science 18(2): 92-106, 2025. Compression garments, utilized in sports and exercise for performance enhancement and recovery, lack sufficient well-controlled studies to overcome any potential placebo effect. Therefore, we tested whether wearing compressive pantyhose (CP) during the Ballet-specific aerobic fitness test (BAFT) would influence performance, recovery, physiological, and perceptual indicators. Additionally, this pilot study tested the feasibility of the research procedures and informed adjustments for the main study. Nine young classical ballerinas attended two sessions on different days: a) wearing CP (pressure of 20-30 mmHg) or b) wearing a placebo pantyhose ([PLA] no compression, containing an illusory …

The Effects Of Augmented Feedback, Focus Of Attention, And Monetary Reward On Vertical Jump Height: A Replication Study, Javad Bakhshinejad, Jasmin C. Hutchinson, Jennifer Murphy, Lydia Trainor, Sarah Friedman, Nicholas Coker

International Journal of Exercise Science

International Journal of Exercise Science 18(7): 13-26, 2025. Reproducibility and replicability of published empirical scientific evidence are fundamental for verifying key findings, identifying errors and/or boundary conditions, and upholding rigorous research standards. For this replication study, the primary goal was to assess the replicability of the findings from Wälchli et al. (2016), which investigated the role of augmented feedback (AF), external focus of attention (EF), and reward (RE), as well as a combination of these conditions on countermovement jump height. The original study sample included 18 resistance-trained male and female participants, while this replication included 38 (19 male, 19 female). …

Validity, Reliability, And Sensitivity Of A Commercially Available Barbell Velocity Measuring Device When Performing Selected Exercises., Daniel J. Lawson, Alex A. Olmos, Cody A. Stahl, Marcel Lopes Dos Santos, Jacob R. Goodin, J. Jay Dawes

International Journal of Exercise Science

International Journal of Exercise Science 17(4): 1250-1279, 2024. The aim of this study was to determine the validity, reliability, and sensitivity of a new linear position transducer (LPT) device (RepOne) to a previously validated LPT (Tendo) during the barbell back squat and bench press exercises. Fourteen recreationally resistance-trained individuals (7 males and 7 females) performed three repetitions for the back squat and bench press at loads ranging from 30–90% 1RM. Both devices recorded average (ACV) and peak (PCV) concentric velocities concurrently for every repetition at each load. Significant correlations were observed between RepOne and Tendo during the back squat (PCV: …

Β-Alanine Plus Sodium Bicarbonate Co-Supplementation Does Not Decrease Neuromuscular Fatigue In Swimming, Felipe Alves Ribeiro, Danilo Rodrigues Bertucci, Carlos Augusto Kalva-Filho, Tarine Botta De Arruda, Matheus Silva Norberto, Giovanni Loureiro Raspantini, Ellen Cristini De Freitas, Alessandro Moura Zagatto, Marcelo Papoti

International Journal of Exercise Science

International Journal of Exercise Science 17(2): 648-659, 2024. This study aimed to investigate the effects of chronic β-alanine (βA) plus acute sodium bicarbonate (SB) co-supplementation on neuromuscular fatigue during high-intensity intermittent efforts in swimming. Eleven regional and national competitive-level young swimmers performed a neuromuscular fatigue assessment before and immediately after two 20 × 25-m front crawl maximal efforts every 90 s, performed at pre- and post-4-week co-supplementation. Neuromuscular fatigue was evaluated by percutaneous electrical stimuli through the twitch interpolation technique on the triceps brachii and quadriceps femoris. Performance was defined by the mean time of the 20 efforts and …

Evaluating A Current Athlete Assessment Program, David Fish

Electronic Theses and Dissertations

The primary purpose of this dissertation is to evaluate the effectiveness of a questionnaire designed to assess coaches’ perceptions of an athlete monitoring program. There are four reasons for this examination of perceptions: 1) it may serve as a check for understanding of how the coach takes in the information presented to them, 2) identify any gaps in the knowledge of the coach which the sport scientist may help to fill, 3) can serve to open a dialog with the coach for ways in which the information may be better tailored to help them improve their decision-making, and 4) the …

The Immediate Effects Of Dry Cupping The Lumbar Paraspinals On Range Of Motion And Temperature, Natasha Scavarelli, Paolo Sanzo

International Journal of Exercise Science

International Journal of Exercise Science 17(3): 551-564, 2024. Dry cupping is a therapeutic modality proposed to produce a negative pressure, stretching the skin and underlying tissue. This mechanism is said to promote regional blood flow of oxygenated blood and causing a physiological stretch in the tissue, allowing it to elongate and potentially changing skin temperature. The possible effects of the application to the lumbar spine paraspinal muscles, however, has not been thoroughly examined. The purpose of this pilot study was to explore the immediate effects of dry cupping the lumbar paraspinals on lumbar spine range of motion (ROM) and overlying …

Maximal Aerobic Capacity As A Predictor Of Performance On Acft Total Score Of Rotc Cadets, Anthony M. Acevedo, Zachary Zeigler, Bridget F. Melton

International Journal of Exercise Science

International Journal of Exercise Science 17(4): 429-437, 2024. The Army Combat Fitness Test (ACFT) is a newly developed test that assesses the combat readiness of U.S. Army soldiers. The purpose of this cross-sectional study is to determine if VO_2max can predict performance outcomes of the ACFT in ROTC cadets. This understanding can provide a better understanding of the aerobic demands of the ACFT. Cadets (50 males, 14 females; aged 21.43 ± 4.10 years) completed the 6-event ACFT (maximum trap-bar deadlift [MDL], standing power throw [SPT], hand-release pushups [HRPU], sprint-drag-carry shuttle run [SDC], plank [PLK], and 2-mile run [2MR]). The …

The Cardiorespiratory Differences Between Physically Trained Vs Untrained Collegiate Competitive Riffle Athletes, Jakob Rankin

Williams Honors College, Honors Research Projects

This research study will examine the differences in cardiorespiratory response of trained vs untrained physically active collegiate athletes participating in the sport of Competitive Rifle. The goal of this study is to determine how the heart and lungs respond from participation in Competitive Rifle with division one collegiate and intercollegiate club athletes. If successful, this study will help to determine a correlation of athletic performance in the sport of Competitive Rifle and structured physical training. We will also compare the results of males vs females within both division one and club athletes. The final output of this project is to …

Psychophysical Load During The Multistage Marathon Des Sables: A Case Study, Leonidas G. Ioannou, Lydia Tsoutsoubi, Georgios I. Tsianos, Andreas D. Flouris

Journal of Human Performance in Extreme Environments

Introduction: This study investigated the impact of the multistage ultra-marathon event ‘‘Marathon des Sables’’ (MdS) performed in the Sahara Desert on the psychophysical capacity of an athlete. Methods: We collected and analyzed environmental, physiological, and behavioral data from a 39-year-old athlete who participated in the MdS. Specifically, we collected environmental temperature (T_env), upper inguinal skin temperature (T_sk), heart rate, and running speed data. Also, we recorded blood glucose and lactate, thermal comfort, total body water, perceived exertion, and cognitive function at the start, middle, and the end of each race stage. Results: We found significant detrimental …

Efficacy Of Six Weeks Stability Exercises On The Glenohumeral Joint Of Female Tennis Players With Scapular Dyskinesia, Sahar Modares Gorji, Omid Kazemi, Parisa Shahrzad, Paulo H. Marchetti

International Journal of Exercise Science

International Journal of Exercise Science 15(3): 962-973, 2022. Background: Stabilizing exercises reduce pain intensity, improves shoulder position and scapular function, and provides an appropriate strategy for the improvement of scapular dyskinesia. The purpose of this study was to investigate the effect of six weeks of stability exercises (stretching-strengthening) on joint proprioception, strength, and range of motion of the glenohumeral joint in female tennis players with scapular dyskinesia. Methods: Thirty-six female elite tennis players with scapular dyskinesia in both experimental and control groups participated in this study. Goniometer, Isokinetic and Biodex devices were used to evaluate the range of motion, internal …

Acute Dose-Response Of Duration During The Plank Exercise On Muscle Thickness, Echo-Intensity, Peak Force, And Perception Of Effort In Recreationally-Trained Participants, Dani Al Sheikh Aleais, Keanna Sullivan, Paula Ferreira, Priscyla N. Marchetti, Paulo Henrique Marchetti

International Journal of Exercise Science

International Journal of Exercise Science 15(6): 676-685, 2022. The primary purpose of this study was to evaluate the acute effects of different durations of the isometric forearm plank exercise (IFPE) on peak force, echo intensity, muscle thickness, and perception of effort in recreationally-trained participants. Fifteen resistance-trained participants (23±3years, 76.4±6.5kg, 173.3±6.5cm) performed the IFPE with bodyweight in one of three durations in a randomized order: a). 1-min, b). 2-min, and c). 3-min. Muscle thickness (MT), echo intensity (EI), peak force (PF), and rating of perceived exertion (RPE) were measured pre-test and post-test. Two-way repeated-measures ANOVAs (2x3) were used to test differences …

The Effect Of Dietary Nitrate Supplementation On Physical And Cognitive Performance During Load Carriage In Military Cadets, Nicholas C. Bordonie

Masters Theses, 2020-current

Purpose: The purpose of this study was to determine the effects of dietary nitrate supplementation on physical and cognitive performance during exercise conducted under heavy pack load in military cadets. Methods: Ten college-aged males (VO_2max 56.2 ± 3.7 ml/kg/min) consumed 140mL/d of concentrated beetroot juice (BRJ; containing 12.8 mmol of dietary nitrate) or a placebo (PL; flavor, color, energy, and texture-matched with no dietary nitrate) for six days preceding an exercise trial. The trial consisted of 45 min of constant-load exercise on a treadmill at 4.83 km/h and 1.5% grade, followed immediately by a 1.6-km time-trial completed at maximal …

Anaerobic Contributions Are Influenced By Active Muscle Mass And The Applied Methodology In Well-Controlled Muscle Group, Gabriel Luches-Pereira, Carlos A. Kalva-Filho, Marcelo Papoti

International Journal of Exercise Science

International Journal of Exercise Science 15(7): 599-615, 2022. The anaerobic metabolism determination is complex and the applied methodologies present limitations. Thus, the purpose of this study was to investigate the effects of different calculations (MAOD vs. AOD) on the anaerobic contribution using the dynamic knee extension. Twenty-four male were recruited [Mean (SD); age 27 (1) years, body mass 90 (3) kg, height 181 (2) cm]. This study was divided into two independent experiments (EXP_{1: ­}one-legged; EXP₂: two-legged). In both experiments, it was performed a graded exercise test to determine maximal power (MP-GXT); 2-4 submaximal efforts (VO …

Assessment Of Relationships Between External Load Metrics And Game Performance In Women’S Lacrosse, Libby Bynum, Ronald Snarr Jr., Bradley Myers 8931361, Jennifer A. Bunn

International Journal of Exercise Science

International Journal of Exercise Science 15(6): 488-497, 2022. The purpose of this study was to analyse the relationship between external load metrics with game performance for Division I collegiate female lacrosse. Data were collected using microtechnology during 26 games with 13 athletes (attackers n = 5, midfielders n = 8). External load variables included: total distance (TD), distance rate (DR), high-intensity (HI) distance, speed, HI sprints, accelerations, decelerations, metabolic equivalent distance (MED), and sprints. For attackers, goals, points, shots, and shots on goal (SOG) had low, positive associations with TD (r = 0.32 to 0.42) and MED (r …

Acute Ingestion Of A Commercially Available Pre-Workout Supplement Improves Anaerobic Power Output And Reduces Muscular Fatigue, Sotiris Panayi, Andy Galbraith

International Journal of Exercise Science

International Journal of Exercise Science 15(6): 455-472, 2022. The effect of a pre-workout supplement on anaerobic power output and muscular fatigue was examined. 18 participants took part in this double-blinded crossover study, reporting for testing on 3 occasions. Participants completed a 6x6 second repeated sprint test, with 20s recovery between sprints. Anaerobic power output was recorded as the highest power achieved during sprint test. Muscular fatigue was reported as a fatigue index across the six sprints ((maximum power – minimum power) ÷ total sprint time). During a baseline visit, participants consumed 250ml of water 30 minutes prior to testing, whilst …

Lifeguard Performance Skills: A Systematic Review, Paulo Santiago, Filipe Maia, Sandra Santiago, Daniel Duarte, Pedro Teques

International Journal of Aquatic Research and Education

Drowning is one of the leading causes of death worldwide and lifeguards’ action can be regarded as a significant contribution to change that reality. In this regard, the purpose of this systematic review was to identify factors associated with lifeguards’ performance. After extensive research on PsycArticles, PsicBooks, PsycInfo, SportDiscus, Web of Science, PubMed, Scopus and SportDiscus databases, containing the keywords “lifeguard” AND “performance”, “lifeguard” AND “skills” and “lifeguard” AND “drowning”, we obtained 429 research articles. After eliminating duplicates, excluding those that had no relevance to the study, and screening against set criteria, a total of five articles were fully reviewed. …

Muscle Daily Undulating Periodization For Strength And Body Composition: The Proposal Of A New Model, Douglas Leão Peixoto, Bruno Magalhães De Castro, Anderson Geremias Macedo, Christiano Bertoldo Urtado, Paulo Soares Lima, Richard Leite, James W. Navalta, Jonato Prestes

International Journal of Exercise Science

International Journal of Exercise Science 15(4): 206-220, 2022. The traditional linear periodization model is designed for modifications to be performed over several weeks, whereas alterations in the undulating model are applied on a more frequent basis. The study investigated a novel periodization scheme, the muscle daily undulating periodization model (mDUP). Thirty-seven men were randomly assigned into 2 groups: (a) a group that performed 12 weeks of daily undulating periodization with fix overload (DUP-F) resistance training (n = 19) and (b) a group that performed 12-weeks of muscle daily undulating periodization with variation overload (mDUP) (n = 18). Body …

Evaluation Of Air Consumption And Work Efficiency In Structural Firefighters, Emily Lynn Langford

Theses and Dissertations--Kinesiology and Health Promotion

INTRODUCTION: For safe and efficient fireground performance, firefighters (FF) must consume air supplied by the self-contained breathing apparatus (SCBA) efficiently while sustaining high work rates. Firefighter research and fire department physical ability assessments typically quantify performance solely on task completion time (i.e., work rate), failing to consider the critical element of air consumption efficiency, which subsequently impacts the SCBA’s functional work duration. PURPOSES: (Arm 1, Aim #1) To examine variability in air consumption (AC) between FF during standardized pace tasks; (Arm 1, Aim #2) To evaluate AC efficiency (ACE) against a recognized metabolic-work rate concept of economy; (Arm …

Exercise Variability Did Not Affect Muscle Thickness And Peak Force For Elbow Flexors After A Resistance Training Session In Recreationally-Trained Subjects, Ethan Smith, Andre Sepulveda, Vincent G.F. Martinez, Ashley Samaniego, Priscyla N. Marchetti, Paulo H. Marchetti

International Journal of Exercise Science

International Journal of Exercise Science 14(3): 1294-1304, 2021. The purpose of this study is to measure the acute effects of exercise variability on muscle thickness and physical performance after two resistance training (RT) protocols using the same or different exercises in recreationally-trained subjects. Fifteen resistance-trained men (23.1 ± 2.6 years, 83.4 ± 16.6 kg, 173.5 ± 8.3cm) performed one of two RT protocols: SINGLE: six sets of 10RM/two-minutes rest of the unilateral biceps curl exercise using cables or MIX: six sets of 10RM/two-minutes rest for the unilateral biceps curl exercises (cable: three sets and dumbbells: three sets, randomly). Muscle thickness …

Ice Hockey Goaltender Physiology Profile And Physical Testing: A Systematic Review And Meta-Analysis, Viviane Marcotte-L'Heureux, Jérémie Charron, Robert Panenic, Alain Steve Comtois

International Journal of Exercise Science

International Journal of Exercise Science 14(6): 855-875, 2021. This review aims to 1) be the first systematic review and meta-analysis of the literature examining the physiology and assessment of goaltenders, and 2) present a physiological profile of ice-hockey goaltenders. It will 1) highlight physiological differences between goaltenders and players at other positions, 2) determine strengths and weaknesses of ice hockey goaltenders, and 3) offer possible guidelines for strength and conditioning coaches. Six electronic databases were systematically searched in October 2019 using the PRISMA model. A total of twelve scientific articles published in peer-reviewed journals were included. Professional male (PM) goaltenders …

The Effect Of Set Configuration And Load On Post-Activation Potentiation On Vertical Jump In Athletes, Paolo Sirieiro, Igor Nasser, Ward C. Dobbs, Jeff Willardson, Humberto Miranda

International Journal of Exercise Science

International Journal of Exercise Science 14(4): 902-911, 2021. The aim of this study was to compare the effect of post-activation potentiation (PAP) on countermovement jump (CMJ) using different set configurations and loads on conditioning activity (CA) in highly trained athletes. Sixteen national level swimmers participated in this study and performed a total of six visits to the laboratory. The first session was used for familiarization, the second session was utilized to determine five repetitions maximum (RM) in the half squat (HS), and the following four visits consisted of four CA protocols performed in a counterbalanced order. Two CAs were performed …

Training On A Lower Body Positive Pressure Treadmill With Body Weight Support Does Not Improve Aerobic Capacity, David K. Lee, Natalie Maltz, James Becker, Joshua A. Cotter

International Journal of Exercise Science

International Journal of Exercise Science 14(7): 829-839, 2021. This study examined the physiological changes resulting from training on a lower body positive pressure treadmill (LBPPT) at three different levels of body weight support (BWS). Thirty-three healthy college aged students (22.3 ± 3.1 years) completed the study. Participants performed a graded exercise test (GXT) to exhaustion and were placed into one of three experimental groups corresponding to 100%, 75%, and 50% of their normal BW. Participants trained at their experimental BW levels for eight-weeks. Training speed was monitored by heart rate (HR) and speed was adjusted to elicit approximately 60% of …

Acute Effect Of Different Duration Of Foam Rolling Protocols On Muscle Thickness, Pain Pressure Threshold, And Volume Load On Multiple Sets Of Knee Extension, Felipe Alves Brigatto, Enrico Gori Soares, Tiago Volpi Braz, Júlio Benvenutti Bueno De Camargo, Charlini Simoni Hartz, Danilo Rodrigues Batista, Luan Oenning Col, Paulo Henrique Marchetti, Marcelo Saldanha Aoki, Charles Ricardo Lopes

International Journal of Exercise Science

International Journal of Exercise Science 14(3): 742-755, 2021. Previous studies investigated the effects of foam rolling (FR) on measurements of strength and power. However, the acute effect of FR on muscle thickness (MT) and pressure pain threshold (PPT) after multiple sets of resistance exercise remains to be elucidated. The aim of the present study was to examine the effect of one and three minutes of quadriceps FR on muscle thickness (vastus lateralis [VL] and rectus femoris [RF]), pain threshold (VL and RF), and total load lifted (TLL) on multiple sets of knee extension. Nine resistance-trained men (age: 24.8 ± 5.2 …

The Effects Of Concurrent Activation Potentiation On Bat Swing Velocity Of Division Ii College Softball Athletes, Alexis Mace, Charles Allen

International Journal of Exercise Science

International Journal of Exercise Science 13(1): 1630-1637, 2020. As an ethical and practical ergogenic strategy, concurrent activation potentiation (CAP), achieved by remote voluntary contractions (RVC) such as jaw clenching, has been proposed to acutely enhance muscular and athletic performance characteristics. The effects of CAP on bat swing velocity (BSV), an important component for successful hitting in sports such as baseball and softball has yet to be reported in the literature. The purpose of this research was to examine the effects of maximal jaw clenching on BSV in collegiate division II softball players. Thirteen (n = 13) division II softball …

Motivational Coaching Improves Intrinsic Motivation In Adult Fitness Program Participants, Victoria J. Gaesser, William M. Maakestad, Erik S. Hayes, Stephen J. Snyder

International Journal of Exercise Science

International Journal of Exercise Science 13(5): 1167-1178, 2020. The purpose of this study was to measure intrinsic motivation following the implementation of motivational coaching strategies in a semester long personalized adult fitness program. Sixty individuals (40 female/ 20 male, age= 48 ± 15 yrs) participated as clients in an undergraduate exercise training program led by student trainers at Taylor University. The program took place during two consecutive semesters, therefore subject participation ranged from one to two semesters. In addition to personalized exercise prescription, student trainers implemented motivational strategies using a motivational coaching guide aimed at increasing individuals’ overall intrinsic motivation. …

Influence Of Fatigue On Planned Agility Performance In Soccer Players., Sofia K. Jakobsson, Tal Amasay

International Journal of Exercise Science

International Journal of Exercise Science 13(1): 656-666, 2020. We investigated the acute fatiguing effects of sprint interval training (SIT) on change of direction performance in male and female soccer players. A T-test was performed once before (PRE) and twice following (POST 1 and POST 2) the completion of four sets of 4 s cycle ergometer sprints protocol. The sprint intervals were separated by 25 s active recovery. POST 1 was performed approximately 25 s following the final cycle sprint and POST 2 began two minutes after completing POST 1. Repeated measures ANOVA and Bonferroni post hoc tests were used to …

Large Inter-Individual Differences In Responses To A Block Of High Intensity Aerobic Interval Training: A Case Series In National-Level Cyclists And Triathletes, Solfrid Bratland-Sanda, Frank G. Pedersen, Marius N. Haave, Jan Helgerud, Øyvind Støren

International Journal of Exercise Science

International Journal of Exercise Science 13(2): 480-487, 2020. The aim was to investigate individual responses on VO_2maxand performance to a block of high intensity aerobic interval training (HIIT) in national-level endurance athletes. METHODS: National-level cyclists and triathletes (five men and two women, 31 ± 3.3 years, VO_2max65.1 ± 3.3 ml·kg^-1·min^-1) conducted 14 HIIT sessions (4x4 min uphill running at 90-95% maximal heart rate) in nine days during preseason. VO_2maxin running and cycling, lactate threshold (LT) in cycling, oxygen cost of cycling (C_C), and a cycling time-trial (TT) were …